Abstract:
:A new method is presented to describe the low shear rate behavior of blood. We observed the response of a thin layer of sedimenting blood to a graded shear stress in a wedge-shaped chamber. The method allows quantitation of the degree of phase separation between red cells and plasma, and extracts the yield stress of the cell phase as a function of hematocrit. Our studies showed that the behavior of normal human blood underwent a transition from a solid-like gel to a Casson fluid. This transition began at the Casson predicted yield stress. The viscoelastic properties of blood were examined at shear stresses below the yield stress. The measured Young's elastic moduli were in good agreement with published data. The yield stress of blood showed a linear dependence on hematocrit up to 60%, and increased more rapidly at higher hematocrit.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Morris CL,Smith CM 2nd,Blackshear PL Jrdoi
10.1016/S0006-3495(87)83210-1subject
Has Abstractpub_date
1987-08-01 00:00:00pages
229-40issue
2eissn
0006-3495issn
1542-0086pii
S0006-3495(87)83210-1journal_volume
52pub_type
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